As she stopped briefly on Corporation Street and waited to cross the road, the offender sexually assaulted her.

The incident was caught on CCTV, which police have released to track down the man responsible.

The offender was described as white, in his 50s, between 5ft 8in and 6ft tall, with a medium build, dark grey stubble and moustache.

He was wearing a dark coloured beanie hat, a dark coat and a rucksack.

Constable Rebecca Lovekin said: “This was a predatory attack that came about after this offender followed the victim down the street.

“He waited until she was trapped between the busy crossing and him before sexually assaulting this terrified woman. She leapt into the busy road to escape him, putting herself in further danger, and the offender walks away. If you recognise this man, help us prevent any further attacks and come forward to police.”